Breast surgery method and apparatus

ABSTRACT

A surgical apparatus for cutting a tissue mass comprising an elongated housing having a distal portion, a rotatable shaft positioned in the elongated housing, and a plurality of flexible electrocautery cutting blades extending from the housing, wherein the plurality of cutting blades are radially expandable from a first position defining a first diameter to a second larger diameter and the blades are rotatable and transmit electrical energy to cut the tissue mass.

CROSS-REFERENCE TO RELATED PATENT APPLICATION

This patent application is based on and entitled, under 35 USC 120, tothe benefit of the filing date of U.S. provisional application60/053,664 filed 24 Jul. 1997 by James F. McGuckin, Jr. and entitled“Minimal Access Breast Surgery Apparatus, and Method”.

FIELD OF THE INVENTION

This invention relates to surgical apparatus and methods for obtaining asubcutaneous target mass having varied shape and dimension.

BACKGROUND OF THE INVENTION AND DESCRIPTION OF THE PRIOR ART

Modern medical diagnostics increasingly rely on complex imagingtechnologies to identify abnormal conditions and/or masses within thehuman body. Such technologies as magnetic resonance imaging (MRI),ultrasonics, computerized axial tomography (CAT scan), and mammogramx-rays, aid medical personnel in the initial identification of areaswithin the body exhibiting potentially dangerous, abnormal biologicalactivity. The beneficial aspect of these technologies is their abilityto image biological structures interior to the human body, providing anon-invasive tool useful in facilitating preliminary diagnosis andtreatment of detected anomalies.

Detected subcutaneous biological growths, masses, etc. once identifiedgenerally require complete surgical excision or at the very least anopen biopsy procedure.

Small masses such as calcifications encountered in breast tissue aregenerally removed in their entirety. The process of excising the mass isan invasive process, performed either during exploratory surgery orutilizing specifically designed surgical apparatus. The retrievedspecimen is subsequently pathologically analyzed to determine itsbiological properties, i.e. benign or malignant.

Several types of apparatus are known for use in removing portions ofsubcutaneous masses in breast tissue targeted by these imagingtechniques. However, these apparatus generally either obtain only smalltissue specimens from the main mass or cause significant surfacescarring due to the size of the incision necessary to remove the masswith a safe resection margin.

One type of specimen retrieval is performed with needle aspirationdevices. These devices have a needle with an end hole. The needle isadvanced to a desired location where a sample specimen is obtained viasuction. Size and quality of specimens obtained by these devices areoften poor, requiring multiple sampling of each desired target mass.Moreover, tissue encountered along the path to the desired location isunavoidably removed. A hollow channel is created upon withdrawal of thedevice from the patient, thereby allowing “seeding” of the hollowchannel removal tract with abnormal cells. Some needle systems utilizean enlarged needle end hole, creating a boring probe which obtains agreater portion of tissue. This lessens the likelihood that the specimenwill be too small but increases the amount of surface scarring due tothe larger size incision required.

The percutaneous incisions needed when multiple needle channels or largeneedle bore channels are used often result in significant scarring,dimpling and disfigurement of surface tissue.

Needle side cutting devices have a blade extending around thecircumference of a hollow needle shaft. The shaft and blade are axiallyrotated around the skin entry site, allowing a larger overall specimento be excised. Target tissue is sliced and a non-contiguous specimen isobtained due to the spiral blade path. While these needle side cuttingdevices facilitate capture of larger sample specimens, they requireresection of a relatively large core of tissue between the incision andthe specimen desired to be resected. Additionally, needle side cutdevices result in irregularly shaped specimens and subcutaneous cavitieshaving irregular and/or bleeding margins.

Hence, the known devices are particularly ill suited in retrievingtissue masses from the female breast, due to the interest in preservingcosmetic integrity of the surface tissue as well as the inability of theknown devices to remove most masses/calcifications during a singleapplication.

SUMMARY OF THE INVENTION

This invention provides surgical apparatus and methods where size andshape of subcutaneous tissue identified for excision is minimallydependent on dimensions of the percutaneous incision. The apparatus andmethods have specific utility in breast surgery.

In one of its aspects this invention provides apparatus for excision ofthe subcutaneous target tissue mass through a cutaneous incision smallerthan maximum transverse dimension of the tissue mass excised where theapparatus includes an axially elongated member including cutaneoustissue piercing means at one end and means connected to the elongatedmember and being radially expandable relative thereto for cutting acircumferential swath of radius greater than maximum transversedimension of the elongated member and greater than maximum transversecross-sectional dimension of the target tissue mass in order to separatethe target tissue mass from surrounding tissue for excision thereofthrough the incision. The apparatus may further include an expandableaseptic shield concentric with the elongated member and axially slidablyadvanceable over the cutting means when in the radially expandedconfiguration, to collectibly bag the target tissue mass detached fromthe patient by the cut circumferential swath, for aseptic removal in anaxial direction together with the elongated member through the incisionresulting from entry of the cutaneous tissue piercing means.

The apparatus may yet further include a sheath which is axially slidablyconcentric with the elongated member and connected to first ends of thecutting means for expanding the cutting means from generally linear andaxial orientation to a curved basket-like orientation by axial movementrelative to the elongated member.

In yet another of its aspects the invention provides apparatus forexcision of a sub-cutaneous target tissue mass through a cutaneousincision smaller than maximum transverse dimension of the tissue massexcised where the apparatus includes an axially elongated member throughwhich cutaneous tissue piercing means may be extended to emerge at oneend thereof. The apparatus further includes means insertable through theelongated member which is radially expandable relative to the elongatedmember for cutting a conical swath having base radius greater thanmaximum transverse dimension of the elongated member and greater thanmaximum transverse cross-sectional dimension of the target tissue mass,for separating the target tissue mass from surrounding tissue forremoval thereof through the incision. In this embodiment of theinvention the apparatus further preferably includes expandable asepticshield means insertable through the elongated member and advanceableover the path of the cutting means to radially expand and collectiblybag the tissue mass detached from a patient by the conical swath cuttingfor aseptic removal in an axial direction through the elongated memberand the incision resulting from entry of the cutaneous tissue piercingmeans.

In one of its aspects this invention preferably provides such apparatushaving a piercing segment for penetrating a percutaneous entranceincision. The forward edge of the piercing segment preferably separatesbreast tissue in the path of the target tissue to be excised. Thepiercing segment preferably passes through the specimen to be excised,delivering an associated preferably circular array of preferably highlyflexible cutting blades to the interior identified subcutaneous breastgrowth.

The circular array of preferably flexible cutting blades is preferablyradially expanded by action of an attached actuating shaft. The bladesradially expand to preferably cut by electro-cauterizing the breasttissue as they rotate around a defined periphery. The blades preferablyoutwardly expand to envelope the target tissue specimen and axiallyrotate to separate the target tissue growth from surrounding breasttissue. The target tissue growth is excised from surrounding breasttissue outisde the periphery of the circular blade path and ispreferably secured by a snaring membrane placed riding over the circulararray of flexible cutting blades.

The membrane is preferably secured over the blade array through anintegral drawstring assembly contracting the mouth of the snaringmembrane. The membrane-encased blade array is preferably drawn into arecovery sheath and compressed for aseptic removal from the excisionsite.

In a method aspect this invention removes subcutaneous breast growths. Apercutaneous surface incision is prepared for reception of surgicalapparatus. Through use of suitable medical imaging technologies, thecutting apparatus device is guided to the area of the targetsubcutaneous breast growth while preferably maintaining a fixedsubcutaneous reference point. A circular array of blades is thenpreferably radially expanded, preferably forming a cutting basket havingdimensions larger than the target subcutaneous breast growth. Radialexpansion and rotation of the electro-cauterizing blades separates thetargeted growth from surrounding tissue. A snaring membrane advancesover the blade array and is secured by an integral drawstring assembly.A recovery sheath compresses the membrane, encasing the target growth asit is withdrawn from the subcutaneous breast cavity. As a result, agrowth which is large relative to the entrance incision is excised. Inanother of its method aspects this invention provides a procedure forexcision of a sub-cutaneous target tissue mass through a cutaneousincision which is smaller than maximum transverse dimension of thetarget tissue mass to be excised where the procedure includes anadvancing tissue piercing means towards a patient to create an incisionin the patient's skin, slidably advancing cutting means through theincision and into sub-cutaneous tissue until in position to radiallyexpand and cut a circumferential swath around the target tissue masslarger than the incision, cutting a circumferential swatch around thetarget tissue mass thereby separating the target mass from thesurrounding tissue, slidably advancing flexible aseptic containmentmeans over the separated target tissue mass to a position of closureabout the target tissue mass and withdrawing the flexible asepticcontainment means, with the target tissue mass aseptically containedtherewithin, through the incision. The method may further includecollapsing the cutting means after cutting the swath.

In yet another of its method aspects, this invention provides aprocedure for excision of sub-cutaneous target tissue mass through acutaneous incision smaller than maximum transverse dimension of thetarget tissue mass to be excised where the procedure includes advancingtissue piercing means towards the patient to create an incision in thepatient's skin, slidably advancing cutting means through the incisionand into sub-cutaneous tissue until in position to gradually radiallyexpand and cut a conical swath about the target tissue mass larger thanthe incision thereby separating the target tissue mass from thesurrounding tissue, slidably advancing flexible aseptic containmentmeans over the separated target tissue mass to a position of closurearound the target tissue mass and withdrawing the flexible asepticcontainment means with the target tissue mass aseptically containedtherewithin through the incision. The invention in this aspectpreferably further includes radially inwardly collapsing the cuttingmeans, which is preferably wire, after cutting the conical swath and mayyet further include radially inwardly cutting tissue along the base ofsaid cone by a passage of the cutting wire therethrough and thereafterclosing flexible aseptic containment means over about the periphery ofthe cone and the target tissue mass contained therewithin.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side view one embodiment of apparatus manifesting aspects ofthe invention with the cutting blades in radially expanded condition.

FIG. 2 is a side view of the surgical apparatus illustrated in FIG. 1 ofthe cutting blades in their non-expanded condition.

FIG. 3 is a front view of a modified version of the apparatusillustrated in FIGS. 1 and 2 with the cutting blades in a non-expandedcondition as illustrated in FIG. 2.

FIG. 4 is a front view of a modified version of the apparatusillustrated in FIGS. 1 through 3 with the cutting blades in theirradially expanded condition as illustrated generally in FIG. 1.

FIG. 5 is a broken schematic partially sectioned view of female breasttissue with the apparatus illustrated in FIGS. 1 through 4 in positionwithin the breast in the process of removing a target tissue mass fromthe breast with the target tissue mass encased within an aseptic shieldportion of the apparatus.

FIG. 6 is a side view of a portion of apparatus according one preferredembodiment of the invention shown in the course of practicing apreferred method aspect of the invention.

FIG. 7 is a side view of a part of the apparatus illustrated in FIG. 6showing additional parts of one preferred apparatus embodiment of theinvention in the course of practicing the inventive method.

FIG. 8 is a side view of the apparatus illustrated in FIG. 7 showing thesupport struts deployed.

FIG. 9 is a side view of the preferred embodiment of the apparatusshowing the struts deploying about a percutaneous growth.

FIG. 10 is a side view of the preferred embodiment of the apparatusshowing advancement of the cutting wire along a strut margin.

FIG. 11 is a side view of the apparatus shown in FIG. 10 with thecutting wire fully deployed.

FIG. 12 is a side view of the preferred embodiment of the apparatusdepicting a new cutting wire retraction.

FIG. 13 is a side view of the preferred embodiment of the apparatusshowing advancement of the bagging structure.

FIG. 14 is a side view of the preferred embodiment with tissuecontainment bagging completed.

FIG. 15 is a side view of the preferred embodiment of the apparatusshowing the containment sheath deploying.

FIG. 16 is a side view of the preferred embodiment of the apparatusshowing the containment sheath normally deployed.

FIG. 17 is an isometric view of the apparatus shown in FIG. 16.

FIG. 18 is a broken view of the tissue containment bag showing thedrawstring tissue.

FIG. 19 is a side view similar to FIG. 16 but showing the containmentsheath fully deployed.

FIG. 20 is a side view similar to FIG. 19 but showing the containmentsheath being withdrawn.

FIG. 21 is a side view similar to FIG. 19 showing optional use of amedicament bag and a radiological marker

FIG. 22 is a side view similar to FIG. 19 showing optional use of liquidmedication supported in part by the containment sheath.

FIG. 23 is an elevation of a support member.

FIG. 24 depicts the female breast and illustrated the incision resultingfrom practice of the method.

FIG. 25 is partial end elevation taken looking from the right in FIG. 8.

FIG. 26 is partial end elevation taken looking from the right in FIG.10.

FIG. 27 is partial end elevation taken looking from the right in FIG.16.

FIG. 28 is a side elevation of a second preferred embodiment ofapparatus embodying the invention with hook and rod structurefacilitating simultaneous performance of the cutting and bagging steps.

FIG. 29 is a partially sectioned side elevation of the embodiment ofapparatus illustrated in FIG. 28 prior to deployment of the hook and rodstructure facilitating simultaneous performance of the cutting andbagging steps.

FIG. 30 is a partially sectioned side elevation of the embodiment ofapparatus illustrated in FIG. 28 showing deployment of the hook and rodstructure facilitating simultaneous performance of the cutting andbagging steps.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

This invention provides surgical apparatus and methods for excision ofpercutaneous breast tissue. The apparatus has the capability to passthrough an incision substantially smaller than the maximum percutaneoustarget specimen dimension occupying an excision site. In one embodimentthe surgical apparatus preferably cuts the target tissue with anelectro-cauterizing, circular array of flexible cutting blades,preferably collecting the specimen within the periphery of an expandableblade path; thus the complete growth is preferably obtained in a singleprocedure. The tissue is preferably returned as a complete specimen or,alternatively, in segments within a snaring membrane. A recovery sheathis preferably positioned to further encase and compress the blade arrayupon contraction.

Referring to FIG. 1, the illustrated embodiment of surgical apparatus 10includes an inner rotatable shaft 20, a tubular recovery sheath 25, asnaring membrane 30, a circular array of radially flexible andexpandable cutting blades generally designated 50, a membrane drawstring80, a membrane mouth section 27 of recovery sheath 25, a power source 15and a tissue piercing member 65.

Membrane 30 preferably has an inner surface 32 coaxially parallel withshaft 20, and an outer surface 34. Inner surface 32 of membrane 30preferably slidably facingly contacts the outside surface 22 of shaft20. Membrane 30 is adjustably positioned in either the distal orproximate direction through the proximate end of shaft 20.

Tubular recovery sheath 25 preferably includes a distal pleated mouthsection 27, an outer surface 45, and an inner surface 60 facinglycoaxially contacting membrane 30. Inner surface 60 slidably engagesouter surface 34 of membrane 30. shaft 20 defines a rotational axis 12.

Shaft 20 rotates as denoted by arrow 12. Rotatable shaft 20 of surgicalapparatus 10 is preferably rotated manually, through mechanical handcontrol. However, shaft 20 may be operably linked with an electricalmotor, not shown, which may be driven by power source 15.

Circular cutting blade 50 includes individual flexible blades 55 whichare preferably anchored between piercing member 65 and proximate end ofshaft 20. Blades 55 are preferably electro-cauterizing, heated byelectrical power source 15.

The materials utilized to construct surgical apparatus 10 are preferablyradiopaque to be visible using modern medical imaging systems.

Referring to FIG. 2, surgical apparatus 10 is shown with individualflexible blades 55 in their non-expandable, tissue insertionorientation. In this insertion orientation the blades are parallel withand of slightly smaller diameter than tubular recovery sheath 25.Tubular recovery sheath 25 includes a snaring membrane 30 having a mouthsection 27 and a drawstring 80, for drawing membrane 30 closed once ithas been opened. Drawstring 80 is positioned along the distal margin ofmouth section 27.

Mouth section 27 of membrane 30 expands outwardly in response to pullingof a polyvinyl tab or ripcord upon reaching the excision site. Thepolyvinyl tab or ripcord is preferably at the end of shaft 20 to theright, which is not shown in the drawing. The polyvinyl tab or ripcordis not visible in the drawing.

Recovery sheath 25 is preferably advanced over circular array of cuttingblades 50 and preferably secured in place around the cutting blades andthe excised specimen by pulling the drawstring towards the proximate endof shaft 20.

Referring now to FIG. 3, piercing segment 65 is formed to separatesubcutaneous tissue in the path between the surface incision and thegrowth.

FIG. 3 and FIG. 4 show a modification of the embodiment of surgicalapparatus 10 illustrated in FIGS. 1 and 2. In the modificationillustrated in FIGS. 3 and 4, shaft 20 includes an interior channel 21extending forwardly through the center of the cutting blade circulararray 50 and connecting with piercing membrane 65. A shaft stem sectionwhich is not shown connects to a dye port 70 in piercing member 65 foroptional delivery of marking fluid to subcutaneous areas. Dye port 70enables operators of apparatus 10 to deliver marking substances to thesubcutaneous excision site. Alternatively, a titanium clip can beejected from a clip fastening surface 75 for marking excision sites forfuture medical imaging analysis.

As shown in FIG. 4, the circular array 50 of cutting blades 55 expandsradially upon relative moment of shaft 20 in the direction of piercingmember 65, defining a cutting orientation. Flexible cutting blades 55are preferably electro-cauterizing, cutting as they outwardly expand andas they rotate after radially outward expansion. Upon rotation offlexible cutting blades 55 in the direction indicated by arrow A in FIG.4, the target tissue growth is separated from the surroundingsubcutaneous breast tissue and remains within the periphery of thecircular blade path.

As variations, the circular array of flexible cutting blades 50 mayemploy radially expandable ultrasonic cutting means, referred to as“harmonic scalpels”, or laser cutting means.

The method of excising subcutaneous breast target tissue growths isshown in FIG. 5. In FIG. 5 the edges of a surgical site where a growthhas been removed is indicated as 100; removal of the growth has createdsubcutaneous cavity 105. As shown, subcutaneous cavity 105 is separatedfrom a surface incision 126 by an excision distance 95.

In preparation for removing the subcutaneous breast tissue growth,percutaneous tissue is cut to produce an incision 126. A piercing member65 of surgical apparatus 10 is placed at incision 126. An excision pathis created by forcing piercing member 65 through the subcutaneous breasttissue between the percutaneous incision 126 and the identified targettissue growth. The target tissue growth is the desired excision sitewhich is visualized via a medical imaging system such as ultrasound ormammography. The tip of surgical apparatus 10 is advanced until thepiercing segment passes through the growth to be excised.

Once apparatus 10 is properly positioned relative to the target tissuemass as indicated by the medical imaging system, the proximate end ofshaft 20 is urged towards piercing member 65. Flexible cutting blades 55radially expand to define subcutaneous margin 100. The array of flexiblecutting blades 50 is then rotated about the shaft axis as indicated byarrow 12, separating the target tissue growth along margin 100.

Membrane 30 is then advanced over the circular array of cutting blades50 and secured by pulling integral drawstring 80 to the right in FIG. 5towards the end of shaft 20. Drawstring 80 secures the distal margin ofmembrane 30. The mouth 27 of sheath 25 is expanded by the polyvinyl pulltab when drawn towards the end of shaft 20.

Circular array of cutting blades 55, now encased by membrane 30, isdrawn into the mouth of snaring sheath 25 and removed from subcutaneouscavity 105.

In the preferred embodiment shown in FIG. 6, a plurality of guide strutsgenerally designated 150 are advanced through a skin surface incision126 and past a target tissue mass 115 via a tubular housing defining anextrication channel 26. As shown in FIGS. 7 and 8, guide struts 150 areinserted through surface incision 126 and moved to a position to definea conically shaped desired excision margin 100 respecting the targettissue mass 115, shown in FIG. 11. As shown in FIGS. 8 through 10, theextension and configuration of struts 150 from surface incision 126 pasttarget mass 115 creates a gradually expanding subcutaneous retrievalpath referred to as a conical penumbra 95.

As shown in FIGS. 11 through 13, an electro-cauterizing cutting snare155 is advanced along guide struts 150, creating a conically shapedexcision margin.

Referring to FIG. 14, the cutting snare 155 is advanced beyond thelength of the guide struts 150 to where cutting snare 155 is drawnclosed by pulling an integral drawstring 160 towards the exterior of theskin. As shown in FIGS. 15 through 17, mouth 27 of sheath 25 is advancedalong the defined extrication channel 26 and expanded by pulling thepolyvinyl pull tab which is not shown. As shown in FIGS. 18 through 24,guide struts 150 are enveloped by snaring sheath 25 and may be removedfrom subcutaneous cavity through extrication channel 26.

In one preferred practice of the invention as depicted in FIGS. 6through 27 and using the apparatus shown therein, apparatus 200 includesa support conduit designated generally 202 and axially elongating skincutting means 204 having a cutting blade 205 which is insertable throughsupport conduit 202 as illustrated generally in FIG. 6. Skin cuttingmeans 204 and particularly cutting blade 205 to make a suitable incisionin the skin, preferably in the human breast designated generally 246 inFIG. 24 where the skin is designated 224 in the drawing figuresincluding FIG. 6 and FIG. 24. The incision is made to provide access toa target tissue mass designated generally 228 in the drawings which hasbeen previously identified preferably using x-ray mammographictechniques as being dangerous and hence to be removed.

Once a skin incision, designated generally 248 in the drawings, has beenmade by skin cutting means 204 and appropriate use of cutting blade 205thereof, skin cutting means 204 is preferably withdrawn axially throughsupport conduit 202, moving to the left in FIG. 6, and support meansdesignated generally 207 and having a plurality of support membersdesignated generally 206 is inserted axially through support conduit 202and into the sub-cutaneous tissue 226 of the breast as indicatedgenerally in FIG. 7, with the direction of travel of support means 207indicated generally by arrow A in FIG. 7.

As support members 206 of support means 207 are inserted into thesub-cutaneous tissue 226, support members expand 206 radially due toinfluence of resilient spring means 210, illustrated in dotted lines inFIG. 8 and forming a portion of support means 207 to a position wheresupport members 206 define a conical penumbra enveloping target tissuemass 228. The conical penumbra 208 defines planes of incision forremoval of target tissue mass 228 and a medically advisable amount ofsurrounding sub-cutaneous healthy tissue 226.

As support members 206 radially diverge one from another due to theinfluence of resilient spring means 210, remote tips 209 of supportmembers 206 define a circle which in turn defines the base of conicalpenumbra 208. Remaining, proximate ends of support members 206 arepivotally connected to a supporting shaft, not numbered in the drawings,for pivoting rotation thereabout in response to spring 210.

Once support members 206 have been deployed, into the positionillustrated in FIG. 8, the target tissue mass is well within the conicalpenumbra defined by support members 206.

A pair of tissue cutting wire loops 214 are positioned about the basesof support members 206, as illustrated generally in FIG. 9, and aresupported by and emerge from respective support catheters 212, alsoillustrated in FIG. 9. Support catheters 212 are sufficiently rigid thatwhen force is applied in the axial direction to support catheters 212 isindicated by arrows B and B′ in FIG. 9, support catheters 212 move tothe right in FIG. 9 advancing tissue cutting wire loops 214 along theouter periphery of support members 204 as depicted generally in FIG. 10.

As support catheters 212 are moved to the right in FIGS. 9 and 10,additional lengths of tissue cutting wires 214 is supplied throughsupport catheters 212 so that tissue cutting wires 214, which are in theform of loops about the exterior surfaces of support members 206 asillustrated in FIG. 10, can enlarge as the circumference of the conicalpenumbra, measured about the slant surface of the conical penumbradefined by support members 206 as illustrated in FIG. 10, increases.

Support catheters 212 are urged to the right in FIG. 10 until tissuecutting wire loops 214 pass the remote tips 209 of support members 206and define a pair of essentially coincident and in any event concentriccircles forming the base of conical penumbra 208.

Once tissue cutting wire loops 214 have reached this position due tomovement of support catheters 212, the. wire forming tissue cutting wireloops 214 are drawn to the left, through respective support catheters212. This causes the respective tissue cutting wire loops 214 each tocinch together as the wires are withdrawn as indicated generally byarrows C, C′ in FIG. 11. As the tissue cutting wires are drawn to theleft in FIG. 11 _(t)hrough respective support catheters 212, the wireloops each cinch together thereby cutting circular incisions through thesub-cutaneous tissue; this action is illustrated generally in FIG. 11where the respective tissue cutting wire loops are shown partially, butnot completely, cinched. Two wire loops are preferable, for symmetricalapplication of force.

Once tissue cutting wire loops 214 have been completely cinched and thewires withdrawn to the position illustrated in FIG. 12 by continuallydrawing the respective tissue cutting wires 214 in the directionsindicated by arrows D, D′ in FIG. 12, the conical penumbra 208 definesplanes of incision created by action of tissue cutting wire loops 214where those planes of incision are shown in dotted lines in FIG. 12.Note that two dotted lines are shown at the extreme right of FIG. 12 toindicate that two circular planar incisions created by action ofrespective tissue cutting wire loops 214. Desirably, these two circularplanar incisions are essentially congruent one with another.

Once tissue cutting wire loops 214 have been completely withdrawn intothe position illustrated in FIG. 12, a suitable tissue containment bagstructure 216 is advanced outwardly of support conduit 202, around theouter periphery of support means 207 and particularly support members206. Tissue containment bag 216 preferably has a pair of drawstrings218, which may be metal, suture material, suitable plastic monofilamentsand the like, which are sewn or threaded into tissue containment bag 216proximate the vertical right-hand margin thereof appearing in FIG. 13.Drawstrings 218 have extremity portions 219 illustrated in FIG. 13.

Once tissue containment bag 216 has been advanced so that its margin 217has traveled inwardly with respect to the breast past the remote tips209 of members 206, to the position generally corresponding to the baseof conical penumbra 208, drawstring extremities 219 are pulled to theright in FIGS. 13 and 14, thereby causing looped drawstrings 218, 218′to close margin 217 of bag 216, causing margin 217 to circularly gatheras shown in FIG. 14.

Once margin 217 of bag 216 has been circularly gathered therebyeffectively closing bag 216 about the target tissue mass 228 ofinterest, an expandable sheath 230 is advanced through the interior ofsupport conduit 202 about tissue containment bag 216 with expandablesheath 230 moving in the direction indicated by arrow F in FIG. 15.Expandable sheath 230 has a pleated expandable portion 231, which isresilient and seeks to expand radially outwardly to relieve internalstresses such that upon expandable portion 231 reaching terminus 203 ofsupport conduit 202 which is within sub-cutaneous tissue 226, expandableportion 231 expands radially into the configuration illustratedgenerally in FIG. 16. Expandable portion 231 of sheath 230 is preferablypleated, as depicted in FIG. 17.

Expandable sheath 230 and particularly expandable portion 231 thereofprovides support in the form of radially inwardly directed force ontissue containment bag 216 as bag 216 with target tissue mass 228enveloped therein is pulled to the left in FIGS. 16, 19 and 20 asindicated generally by arrows G in FIG. 19 and arrow H in FIG. 20. Theradially inward force provided on tissue containment bag 216 and targettissue mass 228 contained therein by expandable sheath 230, as tissuecontainment bag 216 is pulled to the left in FIG. 19, compresses tissuemass 228 into a smaller volume and essentially squashes tissue mass 228into a longitudinally elongated form for passage through support conduit202. Application of the radial force to tissue mass 228 reduces thetransverse cross-sectional dimension of tissue mass 228 to at least thediameter of support conduit 202 as tissue containment bag 216 is drawnthrough the funnel-shaped expandable portion 231 of sheath 230 and intothe interior of support conduit 202.

Once bag 216 and tissue mass 228 contained therein have been removedfrom the sub-cutaneous tissue, expandable sheath 230 may be removed bypulling it in the direction indicated by arrow H in FIG. 20.

Optionally, while expandable sheath 230 is in position and perhaps onlypart way removed from the resected area of interest, a medicament bag232 may be inserted into the resected area through the interior ofsupport conduit 202 and through expandable sheath 230, as indicated inFIG. 21. This may provide means for supplying radioactive gas to provideradiation therapy to the resected area. Additionally, a radiographicmarker depicted as 236 may be implanted into the resected area ofinterest, using the balloon or otherwise while expandable sheath 230remains in the area of the resection. As an additional option whileexpandable sheath remains in position thereby maintaining a void in theresected area of the sub-cutaneous tissue, liquid medication indicatedschematically as 234 in FIG. 22 may be supplied to the resected area. Insuch case expandable sheath maintaining the resected tissue in aspaced-apart condition facilitates application of the liquid medicationto all parts of the resected volume.

Utilizing the method and apparatus as described hereinabove results in asmall, tunnel like incision approaching the skin of the breast with alarger, resected mass being removed therefrom; the resulting internalincision is depicted 244 in FIG. 24.

Support members 206 preferably have metallic tips to provide radiopaquecharacteristics as indicated by 230 in FIG. 23 and may also havemetallic or other radiopaque marker bands indicated as 248 in FIG. 23.Central portions 242 of support members 206 are preferably radiolucentas indicated by the stippling in FIG. 23.

In FIGS. 28 through 30 the curing wire and bag are connected by hook androd structure as illustrated.

1. Apparatus for excision of a sub-cutaneous target tissue mass through a cutaneous incision smaller than maximum transverse dimension of the tissue mass excised, comprising: a. an axially elongated housing; b. tissue piercing means slidably resident within said housing; c. means connected to said elongated hosing and being resiliently radially expandable relative thereto for cutting a conical sheath having radius greater than maximum transverse dimension of said elongated housing and greater than maximum transverse cross-sectional dimension of said target tissue mass to separate said target tissue mass from surrounding tissue for excision thereof through said incision. 2-55. (canceled) 